Trial Outcomes & Findings for Clinical Study of Real Time Colorectal Polyp Diagnosis During Colonoscopy - the VALID Colonoscopy Study (NCT NCT01288833)

Results Overview

Measure of the percentage of accurate high confidence predictions by the endoscopist in the differentiation of neoplastic from non-neoplastic colorectal lesions, using the high definition NBI colonoscopy with and without close focus features. High confidence was assigned if the polyp had one or more features of Type 2 (neoplasia) or Type 1 (nonneoplasia) in the NICE classification and no features associated with the other histology Note: one patient may have multiple polyps.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

558 participants

Primary outcome timeframe

At the time of procedure

Results posted on

2018-06-01

Participant Flow

Participant milestones

Participant milestones
Measure	Close Focus HD NBI Colonoscopy System Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System Use of standard focus for optical diagnosis
Overall Study STARTED	277	281
Overall Study COMPLETED	277	281
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Clinical Study of Real Time Colorectal Polyp Diagnosis During Colonoscopy - the VALID Colonoscopy Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Close Focus HD NBI Colonoscopy System n=277 Participants Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=281 Participants Use of standard focus for optical diagnosis	Total n=558 Participants Total of all reporting groups
Age, Continuous	63 years STANDARD_DEVIATION 7.7 • n=5 Participants	62.4 years STANDARD_DEVIATION 8.7 • n=7 Participants	62.7 years STANDARD_DEVIATION 8.2 • n=5 Participants
Sex: Female, Male Female	16 Participants n=5 Participants	12 Participants n=7 Participants	28 Participants n=5 Participants
Sex: Female, Male Male	261 Participants n=5 Participants	269 Participants n=7 Participants	530 Participants n=5 Participants
Indication Screening	104 Participants n=5 Participants	106 Participants n=7 Participants	210 Participants n=5 Participants
Indication Surveillance	121 Participants n=5 Participants	123 Participants n=7 Participants	244 Participants n=5 Participants
Indication Symptoms	52 Participants n=5 Participants	52 Participants n=7 Participants	104 Participants n=5 Participants

PRIMARY outcome

Timeframe: At the time of procedure

Population: We analyzed all diminutive sized polyps to assess the number of polyps that endoscopists were able to make an accurate high confidence optical diagnosis. High confidence was assigned if the polyp had one or more features of Type 2 (neoplasia) or Type 1 (non-neoplasia) in the NICE classification and no features associated with the other histology.

Measure of the percentage of accurate high confidence predictions by the endoscopist in the differentiation of neoplastic from non-neoplastic colorectal lesions, using the high definition NBI colonoscopy with and without close focus features. High confidence was assigned if the polyp had one or more features of Type 2 (neoplasia) or Type 1 (nonneoplasia) in the NICE classification and no features associated with the other histology Note: one patient may have multiple polyps.

Outcome measures

Outcome measures
Measure	Close Focus HD NBI Colonoscopy System n=530 Polyps analyzed Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=445 Polyps analyzed Use of standard focus for optical diagnosis
Rate of Accurate High Confidence Polyp Histology Predictions by the Endoscopist in the Two Groups.	75.3 Percent of accurate HC predictions Interval 71.3 to 78.9	63.1 Percent of accurate HC predictions Interval 58.5 to 67.6

SECONDARY outcome

Timeframe: At the time of procedure

Measure the cost of colonoscopy with macroscopic histopathologic diagnosis of colorectal lesions compared to colonoscopy with conventional microscopic histopathologic diagnosis, on the lesions that were managed based on an accurate endoscopic diagnosis. A reduction in pathology specimens may improve the efficiency of the procedure and has direct pathology cost savings (as well as indirect savings, which were not measured).

Outcome measures

Outcome measures
Measure	Close Focus HD NBI Colonoscopy System n=277 Participants Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=281 Participants Use of standard focus for optical diagnosis
Cost	241 Specimen bottles that could be omitted	0 Specimen bottles that could be omitted

SECONDARY outcome

Timeframe: At time of procedure

Population: 975 total polyps were found with high confidence predictions made on 774 of them.We assessed diagnostic performance of the high confidence predictions. High confidence was assigned if the polyp had one or more features of Type 2 (neoplasia) or Type 1 (nonneoplasia) in the NICE classification and no features associated with the other histology.

Compare the diagnostic characteristics (sensitivity, specificity, positive predictive value and negative predictive value) using the high definition narrow band imaging colonoscopy with and without close focus features. Accuracy: number of endoscopic predictions of adenomatous polyps histologically confirmed to be adenomatous/number of predicted hyperplastic polyps confirmed to be hyperplastic out of all polyps Sensitivity: number of endoscopic predictions (optical diagnosis) of adenomatous (neoplastic) polyps out of all histologically confirmed polyps Specificity: number of endoscopic predictions of hyperplastic (non-neoplastic) polyps out of all histologically confirmed polyps PPV: number of histologically confirmed adenomatous polyps out of all endoscopic predictions of adenomatous polyps NPV: number of histologically confirmed hyperplastic polyps out of all endoscopic predictions of hyperplastic (non-neoplastic) polyps Note: a patient may have multiple polyps

Outcome measures

Outcome measures
Measure	Close Focus HD NBI Colonoscopy System n=451 Polyps analyzed Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=323 Polyps analyzed Use of standard focus for optical diagnosis
Diagnostic Characteristics Accuracy	88.5 percentage of high confidence prediction Interval 85.2 to 91.3	87.0 percentage of high confidence prediction Interval 82.8 to 90.5
Diagnostic Characteristics Sensitivity	98.2 percentage of high confidence prediction Interval 95.5 to 99.3	95.2 percentage of high confidence prediction Interval 90.8 to 97.6
Diagnostic Characteristics Specificity	73.9 percentage of high confidence prediction Interval 66.7 to 80.0	75.7 percentage of high confidence prediction Interval 67.5 to 82.5
Diagnostic Characteristics PPV	85.0 percentage of high confidence prediction Interval 80.5 to 88.8	84.4 percentage of high confidence prediction Interval 78.7 to 89.0
Diagnostic Characteristics NPV	96.4 percentage of high confidence prediction Interval 91.8 to 98.8	92.0 percentage of high confidence prediction Interval 85.3 to 96.3

SECONDARY outcome

Timeframe: At the time of procedure

Compared the accuracy of predicted versus actual surveillance colonoscopy interval recommendations by determining number of patients with correct surveillance interval recommendation.

Outcome measures

Outcome measures
Measure	Close Focus HD NBI Colonoscopy System n=277 Participants Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=281 Participants Use of standard focus for optical diagnosis
Accuracy of Predicted Versus Actual Surveillance Intervals Predicted (optical diagnosis)	259 Participants	259 Participants
Accuracy of Predicted Versus Actual Surveillance Intervals Actual (histopathological diagnosis)	277 Participants	281 Participants

SECONDARY outcome

Timeframe: At time of procedure.

Population: 975 total polyps were found and we were able to make high confidence predictions on 774 of them.

Examine the impact of a learning curve (i.e. NPV of high confidence at each of endoscopist's first 50% of exams versus last 50% exams to endoscopically predict polyp histology). NPV is defined as "number of histologically confirmed hyperplastic polyps out of all endoscopic predictions of hyperplastic (non-neoplastic) polyps.

Outcome measures

Outcome measures
Measure	Close Focus HD NBI Colonoscopy System n=530 Diminutive polyps Use of close focus to make optical diagnosis Close focus HD NBI Colonoscopy System: Technically improved colonoscope with close focus high definition narrow band imaging. Optical specifications include a 2mm near field focal depth.	Current HD NBI Colonoscopy System n=445 Diminutive polyps Use of standard focus for optical diagnosis
Learning Curve First half	94.9 percentage of high confidence prediction Interval 87.5 to 98.6	88.0 percentage of high confidence prediction Interval 75.7 to 95.5
Learning Curve Second half	96.7 percentage of high confidence prediction Interval 88.5 to 99.6	95.8 percentage of high confidence prediction Interval 88.3 to 99.1

POST_HOC outcome

Timeframe: 5 to 10 years after colonoscopy

Compare the advanced pathology and colon cancer incidence at surveillance colonoscopy of the groups who underwent high definition narrow band imaging colonoscopy with and without close focus features, and more specifically who underwent macroscopic versus microscopic polyp management. This applies if we bring the patient back after 5 years, we have not collected the data yet.

Outcome measures

Outcome data not reported

Adverse Events

Close Focus HD NBI Colonoscopy System

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Current HD NBI Colonoscopy System

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Tonya Kaltenbach

San Francisco VA Medical Center

Phone: 415-221-4810

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place